Pourer pipes of this classification are generally available in commerce. In their case the single vent passage is arranged symmetrically in relation to a plane of symmetry of the pourer pipe and provided in the region of the sector of the outer wall which is remote from the geometrical centre of the crank of the end part. This design is adapted to the long-standing formation hitherto of filler pipes, especially of motor car fuel tanks, in which the filler pipes extended originally vertically and later at an inclination of up to 45.degree. to the vertical. The filter pipes however extend ever more frequently with increasingly acuter angles in relation to the horizontal, which compels introducing the pourer pipe into the filler pipe so that the vent passage lies downwards and thus can no longer fulfill its function.
Since however filler pipes continue to occur in various inclinations, a greater flexibility has been sought in that partially flexible pourer pipes were made. This led to expensive bellows-fold-type constructions unfavourable to production techniques, which moreover have only inadequate wall thicknesses and therefore can easily be damaged. Furthermore, it is very useful if in the case of a can size of above 10 liters a large part of the weight can be supported through the pourer pipe on the filler pipe. Naturally, this possibility does not exist in the case of a flexible pourer pipe.